Various types of electrocautery devices for incising and cauterizing body tissue are known and used in the medical field. Typically, such devices include a conductive blade or needle which serves as one electrode in an electrical circuit which is completed via a grounding electrode coupled to the patient. Incision of tissue is accomplished by applying a source of electrical energy (most commonly, a radio-frequency generator) to the blade. Upon application of the blade to the tissue, a voltage gradient is created, thereby inducing current flow and related heat generation at the point of contact. With sufficiently high levels of electrical energy, the heat generated is sufficient to cut the tissue and, advantageously, to simultaneously cauterize severed blood vessels.
It is widely recognized in the prior art that the often substantial amount of smoke produced by electrocauterization of tissue is at least unpleasant, and in some cases distracting or even hazardous to the operator and other attending medical personnel. As a result, it has been proposed, and is common, to provide an electrocautery device with smoke-aspirating capabilities, such that the smoke produced from electrocauterization is quickly withdrawn from the area of incision. Smoke aspiration may be accomplished by providing, in the handle of the electrocautery device near the electrocautery blade/electrodes an inlet port to be coupled to a vacuum or suction source. Examples of this are described in U.S. Pat. No. 4,307,720 to Weber, Jr., entitled "Electrocautery Apparatus and Method and Means for Cleaning the Same;" in U.S. Pat. No. 5,242,442 to Hirschfeld, entitled "Smoke Aspirating Electrosurgical Device;" and in U.S. Pat. No. 5,269,781 to Hewell, entitled "Suction Assisted Electrocautery Unit."
It has also been recognized in the prior art that the accumulation of coagulated blood, tissue rubble, and other debris on the electrode/blade of an electrocautery device can present a problem for the operator, necessitating the periodic cleaning of the blade, e.g., by wiping the blade over sterilized gauze or the like. This is generally regarded as undesirable, since the need to clean the electrode/blade tends to interrupt the incision procedure and increases the risks associated with contamination of the blade or the incision, damage to the blade, injury to the operator, and the like. To address this problem, it has been proposed in the prior art to provide an electrocautery instrument in which the electrode/blade is in slidable engagement with the instrument's handle, such that when the blade is retracted into the hand, any adhering debris automatically scraped off onto the tip of the handle. Such an instrument is proposed in the above-referenced Weber, Jr. '720 patent. While this arrangement may have some benefit, it still may be necessary to wipe off the tip of the handle once the blade is retracted. It is believed that a more direct and effective approach to the problem would be to reduce the amount of debris created during the electrocautery process, thereby eliminating or at least reducing the need to clean the electrode/blade.